This invention was developed to improve the operations of the conventional automotive downdraft carburetor, in order to provide more efficient operating characteristics and to produce a more effective air/fuel processing system which should improve greatly, the gasoline efficiency of the automotive internal combustion engine. The invention was developed under the premise that any improvements made to provide more efficient carburetion would likewise improve the gasoline efficiency of the engine. As a secondary objective, the reduction of unburned hydrocarbon pollutants was considered and should be an appreciable by-product of an efficient air/fuel processing system which increases fuel efficiency of the gasoline internal combustion engine.
The process of carbureting the air and gasoline fuel in the conventional downdraft carburetors, operating today's automotive internal combustion engines, is primarily responsive to the movements of the throttle valve, normally situated in the throat of the carburetor. The engine acceleration and speed relate to carburetion rate, since the rate of carburetion is effected by the throttle valve rotary movements providing variable control of the rate of intake air flow through the carburetor, which simultaneously induces the fuel into the intake air stream and routed to the engine's combustion chambers. The air flow is generated or drawn into the carburetor by means of the engine cylinders successive intake or suction strokes. Hence, the carburetion process in the conventional carburetor lies in the movements of or is dependent upon the movements of the throttle valve, changing the rate of the intake air flow and dependent upon the fuel induction vacuum.
For instance, at engine idle speed, the throttle valve is normally closed permitting only a very limited quantity of air to be sucked past the throttle valve, thereby setting up a high vacuum in the intake manifold and induction of the gasoline from the idle jet to sustain the engine's operation at idle speed. For low speed acceleration, the throttle valve is rotatably open slightly, exposing the low speed fuel jet. The air being sucked past the low speed jet creates a partial vacuum, inducing gasoline fuel from the low speed jet into the flow of the increased air stream. For full engine acceleration, the throttle valve is rotatably opened fully for induction of the gasoline fuel from the high speed jet. When the throttle valve is first opened fully, the intake manifold vacuum pressure momentarily drops and a higher gasoline input is required. The difference in the pressure between the upper part of the carburetor air horn and the low speed jet is not great enough to continue the induction of gasoline from the low speed jet or induce fuel from the high speed jet in the upper part of the air horn. Consequently, there is a momentary loss of induced fuel. However, the accelerator movements that opened the throttle valve fully and caused the momentary loss of induced fuel, simultaneously triggers the mechanically operated accelerator jet that manually injects a flow of unvaporized liquid gasoline into the carburetor's throat, that vaporizes into the air stream and sustains the engine's high speed operation during the momentary loss of induced fuel. This allows the intake manifold vacuum to stabilize and the air flow to create a vacuum at the high speed jet, inducing gasoline fuel for continuous operation of the engine at the high speed mode.
Each of the jets are serviced by the carburetor's float chamber that stores the liquid gasoline. As the induced liquid gasoline leaves the jets described and enters the air stream, the fuel is theoretically atomized or broken-up into a mist. According to the Encyclopedia Americana, less than half of the gasoline entering the air stream makes the change of phase from the liquid phase to the vaporized or gaseous phase. The unvaporized gasoline in the air stream consists of heavy particles ranging from a fine mist to particles of appreciable size. Of further consequence, during the short time span available during the carburetion process, a thoroughly homogenous mixture of air and gasoline has not been achieved so that all fuel particles can react with the oxygen in the cylinder. Thus, the intake manifold that distributes the air to the various engine cylinders will not necessarily distribute the unvaporized gasoline equally, because the inertia of unvaporized heavy fuel particles is considerably greater than that of air molecules. Consequently, the engine's combustion of the air/fuel mixture is incomplete, with most of the unvaporized gasoline passing through the engine unburned or partially burned and wasted. According to recent reports released by the Environmental Protection Agency (EPA), these unburned or partially burned and wasted gasoline particles are unburned hydrocarbon properties of the spent gasoline and one of the primary sources of automotive pollution.